Elderly man killed, boy fighting for life after Perth house fire

An elderly man has died and a young boy is fighting for his life after being pulled from a burning house in Perth’s south-west.

Initial reports from the scene at Thornlie said they had been killed and another child was missing, however police confirmed to 9NEWS the two occupants had suffered injuries as a result of the blaze and the child was found.

But now authorities have confirmed the man, aged 69, has died while the boy, 4, remains in a critical condition in hospital.

Two people have been rushed to hospital after a fire in Perth's south-east. Picture: 9NEWS (9news)A child was unaccounted for but has now been found. Picture: 9NEWS (9news)

The pair was found unresponsive after fire crews arrived at the Thornlie home at 6.15pm local time (7.15pm AEST) and taken by ambulance to Fiona Stanley Hospital

"The house has been cleared," Police Inspector Dean Snashall told reporters last night.

"There was some early confusion given the time of night and the fact that it was quite a hectic scene to start with.

Police have blocked off the street. Picture: 9NEWS (9news)The arson squad is on scene trying to determine the cause of the blaze. Picture: 9NEWS (9news)

"But we've now confirmed there was only two people in the house and they've both been accounted for.